As one example of such kinds of techniques, a technique in which a connection end of a laser diode (LD) to a 5V power supply line is directly connected to an input port of a CPU for cover open detection is conventionally known. In this technique, an interlock switch is provided for each of the 5V power supply line and a 24V power supply line which supplies power to a motor and, when a cover is opened, power to the LD and the motor is cut off and the cover opening is detected by software.
An image forming apparatus generally includes a plurality of high voltage generators (high voltage loads) which generates different voltages and is supplied with power with different voltages depending on a level of voltage to be generated. Due to a demand for safety and power saving, there is a need for a technique which is capable of cutting off power from a plurality of high voltage loads in interlock with the cover opening. Consideration has been made of a method which switches the power supply ON/OFF using, for example, a switching element for the cutting-off of power from the high voltage loads in interlock with the cover opening. In this case, a method of PWM-controlling the switching element in order to reduce an inrush current which may be generated when the power supply is switched ON may be contemplated. However, this may require a complicated control circuit.
An exemplary embodiment of the present invention may make it possible to provide a technique which is suitable to cut off power from an LD and a high voltage load with a simple configuration. It is another object of the present invention to provide a technique which is suitable to cut off power from a plurality of high voltage generating units with different voltages generated, which are included in a high voltage generating power supply, with a simple configuration.